Lab+Exercise+1

[[image:beaker.jpg]]Use this page to collaborate on the team project for Week 3.
So I was thinking that maybe we should do the density lab or something along the lines of it. Does that sound good to you guys?

I was thinking that a density lab would work it will go along with the stuff I happen to be teaching in that week. ~ Jon

Yeah, that's fine with me. My school is a lot farther than you guys are. We are doing ionic and covalent and we should be starting chemical reactions later this week. Mike

**MISSION OBJECTIVES:** The team must ... (1) identify the apparatus most commonly used in first-year chemistry experiments. ﻿ ﻿Beaker, Graduated Cylinder, Balance, Test Tube, Erlenmeyer Flask, Bunsen Burner, Hot Plate, Stir rod, Spatula, Pipette, Watch Glass, (2) discuss the safety rules associated with the use of such apparatus. ﻿Beaker = used for holding/mixing basic solids and liquids. Keep clean to avoid contamination.  Graduated Cylinder = Accurately measuring a liquid. Keep clean to avoid contamination.  Balance = Used to measure the mass of an object. Keep clean. Zero before every use. Record all digits.  Test Tube = Used for small scale mixing or reacting solids and liquids. When not in use keep in test tube rack to avoid spilling.  Erlenmeyer Flask = Used for holding/mixing gas producing liquids and solids. Do not put face directly over Mouth of flask to avoid over inhalation of fumes.  Bunsen Burner = A gas flame used for heating. Do not touch, Misuse, or leave flame unattended.  Hot Plate = A surface used for heating (commonly can heat to a desired temp.). Do not touch. Keep clean and shut off heat when not in use.  Stir Rod = Used to mix solutions. Keep clean to avoid contamination.  Spatula = Used for handling solids for measurement. Keep clean to avoid contamination. <span style="background-color: #ffffff; color: #3115c6; font-size: 11pt; font-style: normal; font-weight: normal; vertical-align: baseline;"> Pipette = Used for measuring a liquid volume very accurately. Wash out to avoid contamination. Watch Glass = Used for holding/mixing/drying a substance. Keep clean to avoid contamination.

<span style="background-color: transparent; color: #000000; font-family: Arial; font-size: 11pt; font-style: normal; font-weight: normal; margin: 0px; padding: 0px; text-decoration: none; vertical-align: baseline;">(3) design meaningful or purposeful lab activities that use the apparatus. <span style="background-color: #ffffff; color: #0000ff; font-size: 11pt; font-style: normal; font-weight: normal; margin: 0px; padding: 0px; vertical-align: baseline;">﻿__**The Density Lab**__ <span style="background-color: #ffffff; color: #0000ff; font-size: 11pt; font-style: normal; font-weight: normal; margin: 0px; padding: 0px; vertical-align: baseline;"> Various Items will be both weighed for mass and put in water to measure the water displacement for volume. Then density will be determined by D = m/V. The calculations can then be compared to a list of densities for the unknown items to be identified. <span style="background-color: #ffffff; color: #0000ff; font-size: 11pt; font-style: normal; font-weight: normal; margin: 0px; padding: 0px; vertical-align: baseline;"> Equipment = Balance and a Graduated cylinder. <span style="background-color: #ffffff; color: #0000ff; font-size: 11pt; font-style: normal; font-weight: normal; margin: 0px; padding: 0px; vertical-align: baseline;"> The students will learn how to use two basic apparatus by weighing objects in my case using triple beam balances which is a good skill and by measuring displacement of water in the graduated cylinder, learning how to read the bottom of the meniscus and how many sig figs can be used for a specific cylinder.

<span style="background-color: #ffffff; color: #008000; font-size: 11pt; font-style: normal; font-weight: normal; margin: 0px; padding: 0px; vertical-align: baseline;">I agree with what you have written. I would include another activity upon which they have to also use a ruler and measure the volume of the object. This only works for objects with definite size and is easily measurable with a ruler. For instance, in CHE 102 we used pennies because they are easy to measure and past 1982 they have different densities. <span style="background-color: transparent; color: #000000; font-family: Arial; font-size: 11pt; font-style: normal; font-weight: normal; margin: 0px; padding: 0px; text-decoration: none; vertical-align: baseline;">(4) cohesively fit together all lab activities to serve a common goal or describe a common topic.

The common goal is to teach the students basic lab skills and use information learned with scientific notation, significant figures, and density. You could also find a way to incorporate a lesson about scientific method.

Alright so I had some time at school to get this done just let me know this is just kind of a rough draft. I don't know if this is what Swanson wants exactly but I figure it's a start. Let me know what you think and make any changes you see fit. ~ Jon

Overall I think Jon hit the nail in the head. Density labs are a great way to introduce the lab atmosphere without putting them in harms way. They don't have to use any hazardous chemicals and you can observe how they behave in the laboratory. Mike

I think that for the bunsen burner that hair tied back is very important and to wear tight fitting long sleeves or wear short sleeves. Also we should maybe add something about hot glass looks the same as cold glass so be very careful when handling it.